JP4161077B2 - Flow measuring device - Google Patents

Flow measuring device Download PDF

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JP4161077B2
JP4161077B2 JP2005284047A JP2005284047A JP4161077B2 JP 4161077 B2 JP4161077 B2 JP 4161077B2 JP 2005284047 A JP2005284047 A JP 2005284047A JP 2005284047 A JP2005284047 A JP 2005284047A JP 4161077 B2 JP4161077 B2 JP 4161077B2
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passage
flow rate
main
flow
bent portion
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JP2007093422A (en
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裕之 裏町
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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Priority to JP2005284047A priority Critical patent/JP4161077B2/en
Priority to US11/356,162 priority patent/US7530267B2/en
Priority to DE102006012929.6A priority patent/DE102006012929B4/en
Priority to KR1020060026821A priority patent/KR20070036594A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/68Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/68Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
    • G01F1/684Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
    • G01F1/6842Structural arrangements; Mounting of elements, e.g. in relation to fluid flow with means for influencing the fluid flow

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Volume Flow (AREA)

Description

この発明は、流量測定装置に関するものであり、例えば内燃機関の空気の質量流量を測定する装置に関するものである。   The present invention relates to a flow rate measuring device, for example, a device for measuring a mass flow rate of air in an internal combustion engine.

従来の流量測定装置は、流入口から流出口まで複数回屈曲したバイパス通路を備え、内部には白金等の材料で構成された感熱抵抗体が形成された流量検出素子を配設しており、バイパス通路を複数回屈曲させることにより、被計測流体に含まれるダスト等の異物を減速させ、該異物が流量検出素子に高速で衝突するのを防止するようにしている。そして、バイパス通路の流出口は、流入口よりも回路収納部から離れた位置に配置されている(例えば、特許文献1参照)。   A conventional flow rate measuring device includes a bypass passage that is bent a plurality of times from an inlet to an outlet, and a flow rate detecting element in which a thermal resistor made of a material such as platinum is formed is disposed. By bending the bypass passage a plurality of times, foreign matter such as dust contained in the fluid to be measured is decelerated, and the foreign matter is prevented from colliding with the flow rate detection element at high speed. And the outflow port of a bypass passage is arrange | positioned in the position away from the circuit accommodating part rather than the inflow port (for example, refer patent document 1).

特許第3602762号公報Japanese Patent No. 3606022

一般的に、自動車用内燃機関においては、吸入、圧縮、爆発、排気のサイクルを繰り返し行い、また複数のシリンダ気筒で構成されるため、吸入空気の流速は時間的に変動する脈動流となっている。そして、内燃機関の主通路内を流れる主流は、内燃機関の回転数に同期した周波数で脈動しており、その周波数が低い程、主通路軸心を中心とした径方向の流速分布は凸型となり、その周波数が高い程、流速分布は平坦化する。   Generally, in an internal combustion engine for automobiles, a cycle of suction, compression, explosion, and exhaust is repeated, and a plurality of cylinders are used. Therefore, the flow rate of intake air is a pulsating flow that varies with time. Yes. The main flow flowing in the main passage of the internal combustion engine pulsates at a frequency synchronized with the rotational speed of the internal combustion engine, and the lower the frequency, the more the radial flow velocity distribution centered on the main passage axis is convex. The higher the frequency, the flatter the flow velocity distribution.

従来の流量測定装置では、バイパス通路の流入口と流出口が主通路の径方向において離れた位置にある。そこで、従来の流量測定装置を自動車用内燃機関に適用すると、主通路を流れる吸入空気の流量は同じでも、該主通路の径方向における流速分布が内燃機関の回転数に応じて変化するために、吸入空気量が同じにも関わらず、その回転数が変化することでバイパス通路の流入口と流出口の近傍の流速に差異が生じ、バイパス通路内に誘起される流れの流速に差異が生じ、ひいては流量測定装置の検出流量誤差を発生してしまう。   In the conventional flow rate measuring device, the inflow port and the outflow port of the bypass passage are at positions separated in the radial direction of the main passage. Therefore, when a conventional flow rate measuring device is applied to an automotive internal combustion engine, the flow rate distribution in the radial direction of the main passage changes according to the rotational speed of the internal combustion engine even though the flow rate of the intake air flowing through the main passage is the same. Even though the intake air amount is the same, a change in the rotation speed causes a difference in the flow velocity in the vicinity of the inlet and outlet of the bypass passage, and a difference in the flow velocity of the flow induced in the bypass passage. As a result, a detection flow rate error of the flow measurement device is generated.

また、従来の流量測定装置を自動車用内燃機関に適用する場合、少なくとも流入口と流出口を主通路内に突出する必要があり、主通路径方向においてその突出長さが長くなり、ひいては流量測定装置を主通路にプラグインすることにより生じる圧力損失が大きくなってしまう。   In addition, when a conventional flow rate measuring device is applied to an internal combustion engine for automobiles, it is necessary to project at least an inlet and an outlet into the main passage, and the projection length becomes longer in the radial direction of the main passage. The pressure loss caused by plugging the device into the main passage increases.

この発明では、従来技術における上記の問題点を解決するためになされたものであり、特に自動車用内燃機関の吸入空気量を計測する際に、内燃機関の吸入空気に含まれるダスト等の異物が流量検出素子に高速で衝突するのを防止し、耐久性および寿命を向上できるという効果を確保しつつ、内燃機関の回転数に同期した脈動流の周波数が異なり、主通路内の流速分布が異なる場合においても、計測用通路内の流速の変化を抑制して、正確な流量測定を可能にし、また主通路内にプラグインすることにより生じる圧力損失をより小さくできるようにした流量測定装置を提供することにある。   The present invention has been made to solve the above-described problems in the prior art, and in particular, when measuring the intake air amount of an internal combustion engine for automobiles, foreign matters such as dust contained in the intake air of the internal combustion engine. The frequency of the pulsating flow synchronized with the rotational speed of the internal combustion engine is different and the flow velocity distribution in the main passage is different while ensuring the effect of preventing collision with the flow rate detection element at high speed and improving durability and life. Even in some cases, the flow rate measurement device that suppresses changes in the flow velocity in the measurement passage, enables accurate flow measurement, and further reduces the pressure loss caused by plugging in the main passage. There is to do.

この発明による流量測定装置は、主通路内に延出され、内部に回路収納部を備えた本体部と、上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、上記計測用通路内に配設された流量検出素子と、上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有している。そして、上記計測用通路は、上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備えている。さらに、上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されている。そして、上記第4通路部が、上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びて上記本体部の延出方向の端面に開口して上記流出口を構成し、上記主流の流れ方向および上記本体部の延出方向を含む平面における断面形状を円形とする通路断面積拡大部が上記第4通路部の上流側に該第4通路部および上記流出口に接続するように形成されている。 The flow rate measuring device according to the present invention extends in the main passage and is formed on the extension side of the circuit storage portion of the main body portion with the circuit storage portion therein, and flows through the main passage. A measurement passage through which a part of the fluid to be measured is circulated, a flow rate detection element disposed in the measurement passage, and a signal stored in the circuit storage unit and driven by the flow rate detection element. And a control circuit. The measurement passage is positioned in the vicinity of the end of the main body in the extending direction, and is directed to the upstream side of the main flow direction of the fluid to be measured. An inlet opening in an orthogonal plane, an outlet located in the vicinity of an end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body, and the inlet A first passage portion extending from the first bent portion to the first bent portion along the mainstream flow direction, and a second bent portion from the first bent portion to the circuit housing portion along a direction orthogonal to the mainstream flow direction. A second passage portion extending to the third bending portion along the main flow direction from the second bending portion, and a direction orthogonal to the main flow direction from the third bending portion. And a fourth passage portion extending in a direction away from the circuit storage portion. . Further, the fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detecting element is disposed in the third passage. The fourth passage portion extends from the third bent portion in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction, and opens to an end surface of the main body portion in the extending direction. And a passage cross-sectional area enlarged portion having a circular cross-sectional shape in a plane including the flow direction of the main flow and the extending direction of the main body portion is formed on the upstream side of the fourth passage portion. It connects with the part and the said outflow port.

この発明によれば、流路をほぼ90°に曲げる第1屈曲部および第2屈曲部が流入口から流量検出素子が配設された第3通路に至る通路中に設けられているので、被計測流体内にダスト等の異物は、第1屈曲部および第2屈曲部に衝突して減速される。そこで、異物が流量検出素子に衝突したとしても、その衝突エネルギーは小さく、流量検出素子の耐久性および寿命が向上される。
また、計測用通路の流入口と流出口が主通路の径方向において近接した位置にあるので、吸入空気量が同じにも関わらず、回転数が変化して主通路内の流速分布が変化しても、計測用通路の流入口と流出口の近傍の流速に差異が生じ難い。そこで、計測用通路内に誘起される被計測流体の流れの流速に差異が生じ難く、流量測定誤差を低減することができる。
さらに、計測用通路の流入口と流出口が主通路の径方向において近接した位置にあるので、主通路の径方向における流量測定装置の延出長さを短くでき、主通路内にプラグインすることにより生じる圧力損失をより小さくできる。
According to the present invention, the first bent portion and the second bent portion that bend the flow path to approximately 90 ° are provided in the passage extending from the inflow port to the third passage where the flow rate detecting element is disposed. Foreign matter such as dust in the measurement fluid collides with the first bent portion and the second bent portion and is decelerated. Therefore, even if a foreign object collides with the flow rate detection element, the collision energy is small, and the durability and life of the flow rate detection element are improved.
In addition, since the inlet and outlet of the measurement passage are close to each other in the radial direction of the main passage, the rotational speed changes and the flow velocity distribution in the main passage changes even though the intake air amount is the same. However, it is difficult for the flow velocity in the vicinity of the inlet and outlet of the measurement passage to be different. Therefore, it is difficult for a difference in flow velocity of the flow of the fluid to be measured induced in the measurement passage, and a flow measurement error can be reduced.
Furthermore, since the inlet and outlet of the measurement passage are close to each other in the radial direction of the main passage, the extension length of the flow rate measuring device in the radial direction of the main passage can be shortened and plugged into the main passage. The pressure loss caused by this can be made smaller.

以下、この発明の実施の形態による流量測定装置について、図面に従って詳細に説明する。   Hereinafter, a flow rate measuring device according to an embodiment of the present invention will be described in detail with reference to the drawings.

実施の形態1.
図1はこの発明の実施の形態1に係る流量測定装置を主通路に取り付けた状態を示す横断面図、図2はこの発明の実施の形態1に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図、図3は図1の流量検出素子周りを示す要部拡大図、図4は図2の流量検出素子周りを示す要部拡大図、図5は図2のV−V矢視断面図である。
なお、横断面とは主通路の軸心と直交する断面の表面を示す。また、図2において、被計測流体の主流は図中に矢印Aで示す方向に流れている。
Embodiment 1 FIG.
1 is a transverse sectional view showing a state in which a flow rate measuring device according to Embodiment 1 of the present invention is attached to a main passage, and FIG. 2 is a state in which the flow rate measuring device according to Embodiment 1 of the present invention is attached to the main passage. 3 is a partially broken side view showing the main part of FIG. 3, FIG. 3 is an enlarged view of the main part showing the periphery of the flow detection element of FIG. 1, FIG. 4 is an enlarged view of the main part showing the periphery of the flow detection element of FIG. It is a VV arrow directional cross-sectional view.
In addition, a cross section shows the surface of the cross section orthogonal to the axial center of a main channel | path. In FIG. 2, the main flow of the fluid to be measured flows in the direction indicated by the arrow A in the figure.

図1乃至図4において、主通路1は、被計測流体が流通する円筒状の管体であり、自動車用内燃機関の場合、通常、樹脂製で、吸入空気濾過装置(図示せず)と一体に構成された吸気通路である。そして、被計測流体は空気となる。この主通路1には、流量測定装置4をプラグインするための挿入穴2が設けられている。   1 to 4, a main passage 1 is a cylindrical tube through which a fluid to be measured flows. In the case of an internal combustion engine for an automobile, the main passage 1 is usually made of resin and integrated with an intake air filtration device (not shown). It is the intake passage comprised in this. And the fluid to be measured is air. The main passage 1 is provided with an insertion hole 2 for plugging in the flow rate measuring device 4.

流量測定装置4は、主通路1内に配置されて被計測流体の一部を流通させる計測用通路5と、計測用通路5内を流通する被計測流体の流量を検出する流量検出素子6と、流量検出素子6を駆動し、その流量検出信号を処理するための制御回路が構成された回路基板7と、流量検出素子6および回路基板7を保持する金属プレート8と、金属プレート8を支持するベース9と、ベース9に近接して配設され、金属プレート8と協働して計測用通路5を構成する計測用通路構成部13と、を有する。   The flow rate measuring device 4 is disposed in the main passage 1 and circulates a part of the fluid to be measured, and a flow rate detection element 6 that detects the flow rate of the fluid to be measured that circulates in the measurement passage 5. The circuit board 7 on which the control circuit for driving the flow rate detection element 6 and processing the flow rate detection signal is configured, the metal plate 8 holding the flow rate detection element 6 and the circuit board 7, and the metal plate 8 are supported. And a measurement passage constituting portion 13 which is disposed in the vicinity of the base 9 and forms the measurement passage 5 in cooperation with the metal plate 8.

流量検出素子6は、流量検出抵抗6bおよび温度補償用抵抗6cからなるセンサ部が矩形平板状の基板6aの表面に形成され、流量検出抵抗6bおよび温度補償用抵抗6cに電気的に接続された入出力端子6dが基板6aの表面の一側に形成されて構成されている。ここで、流量検出抵抗6b、温度補償用抵抗6cおよび入出力端子6dは、基板6aの表面に成膜された白金、ニッケル、鉄・ニッケル合金などの感熱抵抗膜をパターニングして形成される。また、流量検出抵抗6bの形成領域は、基板6aを裏面側から除去して形成されたキャビティ6eによりダイアフラム構造となっている。さらに、流量検出素子6には、流量検出抵抗6bの熱が温度補償用抵抗6cに伝達し難いような熱絶縁手段(図示せず)が施されている。さらにまた、基板6aの材料としては、シリコンあるいはセラミックスなどの電気絶縁材料が用いられる。   In the flow rate detecting element 6, a sensor portion including a flow rate detecting resistor 6b and a temperature compensating resistor 6c is formed on the surface of a rectangular flat substrate 6a, and is electrically connected to the flow detecting resistor 6b and the temperature compensating resistor 6c. An input / output terminal 6d is formed on one side of the surface of the substrate 6a. Here, the flow rate detection resistor 6b, the temperature compensation resistor 6c, and the input / output terminal 6d are formed by patterning a heat-sensitive resistance film such as platinum, nickel, iron / nickel alloy, etc. formed on the surface of the substrate 6a. In addition, the flow detection resistor 6b is formed in a diaphragm structure by a cavity 6e formed by removing the substrate 6a from the back surface side. Further, the flow rate detecting element 6 is provided with a heat insulating means (not shown) that makes it difficult for the heat of the flow rate detecting resistor 6b to be transferred to the temperature compensating resistor 6c. Furthermore, as the material of the substrate 6a, an electrically insulating material such as silicon or ceramics is used.

金属プレート8は、アルミやステンレスなどの金属材料を矩形平板状に成形され、回路基板収納凹部8aおよび流量検出素子収納凹部8bがその表面上に近接して凹設されている。そして、回路基板7が回路基板収納凹部8aに収納され、接着剤により固定されている。また、流量検出素子6が、入出力端子6dを回路基板7側に位置させて流量検出素子収納凹部8b内に収納され、接着剤により固定されている。なお、回路基板7および流量検出素子6は、金属プレート8の表面と同一面位置になっている。   The metal plate 8 is formed of a metal material such as aluminum or stainless steel in a rectangular flat plate shape, and a circuit board housing recess 8a and a flow rate detection element housing recess 8b are provided close to the surface. And the circuit board 7 is accommodated in the circuit board accommodation recessed part 8a, and is being fixed with the adhesive agent. The flow rate detecting element 6 is accommodated in the flow rate detecting element accommodating recess 8b with the input / output terminal 6d positioned on the circuit board 7 side, and is fixed by an adhesive. The circuit board 7 and the flow rate detection element 6 are flush with the surface of the metal plate 8.

ベース9は、主通路1に挿入された際に気密性を確保する接合部10と、接合部10の一側に配設されて回路基板7と外部との信号の授受を行うコネクタ部11と、接合部10から他側に配設された、回路基板収納凹部8aおよび流量検出素子収納凹部8bの回路基板収納凹部8a側を内包する回路収納部12と、を有し、例えばポリブチレンテレフタレート等の樹脂により一体にモールド成形されている。
そして、金属プレート8が、回路基板7および流量検出素子6が取り付けられた状態で、回路基板7および流量検出素子6の入出力端子6d側を回路収納部12内に露出するようにベース9に接着固定されている。そして、金属プレート8の裏面が、ベース9から露出している。
The base 9 includes a joint portion 10 that ensures airtightness when inserted into the main passage 1, and a connector portion 11 that is disposed on one side of the joint portion 10 and exchanges signals between the circuit board 7 and the outside. The circuit board housing recess 8a and the circuit board housing recess 8a of the flow rate detecting element housing recess 8b disposed on the other side from the joint 10 and a circuit housing section 12 including the circuit board housing recess 8a, for example, polybutylene terephthalate It is molded integrally with the resin.
The metal plate 8 is attached to the base 9 so that the circuit board 7 and the flow rate detecting element 6 are attached to the circuit housing portion 12 with the input / output terminal 6d side of the circuit board 7 and the flow rate detecting element 6 being exposed. Bonded and fixed. The back surface of the metal plate 8 is exposed from the base 9.

また、計測用通路構成部13は、例えばポリブチレンテレフタレート等の樹脂により成形されている。そして、計測用通路構成部13が、その一面をベース9から延出する金属プレート8の部位に接着剤などにより固定されている。そして、計測用通路構成部13の一面には、計測用通路溝5aが凹設されており、金属プレート8と協働して通路断面を矩形とする計測用通路5を構成している。なお、計測用通路構成部13は、樹脂によりベース9と一体に成形されてもよい。   Moreover, the measurement channel | path structure part 13 is shape | molded, for example with resin, such as a polybutylene terephthalate. And the measurement channel | path structure part 13 is being fixed to the site | part of the metal plate 8 which the one surface extends from the base 9 with an adhesive agent. And the measurement channel | path groove | channel 5a is recessedly provided in one surface of the measurement channel | path structure part 13, and the measurement channel | path 5 which makes a channel cross section rectangular in cooperation with the metal plate 8 is comprised. In addition, the measurement channel | path structure part 13 may be shape | molded integrally with the base 9 with resin.

この計測用通路5は、図2に示されるように、流入口21、第1通路22、第1屈曲部23、第2通路24、第2屈曲部25、第3通路26、第3屈曲部27、第4通路28、第4屈曲部29、第5通路30および流出口31を備えている。そして、流入口21は、流量測定装置4の反コネクタ部側の端部近傍に、主流の流れ方向Aに対して上流側に向いて開口し、被計測流体を計測用通路5に流入させる。流出口31は、流量測定装置4の反コネクタ部側の端面に開口し、被計測流体を計測用通路5から流出させる。この流量測定装置4の反コネクタ部側の端面は、主流の流れ方向Aと略平行な面である。   As shown in FIG. 2, the measurement passage 5 includes an inflow port 21, a first passage 22, a first bent portion 23, a second passage 24, a second bent portion 25, a third passage 26, and a third bent portion. 27, a fourth passage 28, a fourth bent portion 29, a fifth passage 30, and an outflow port 31. The inflow port 21 is opened in the vicinity of the end of the flow rate measuring device 4 on the side opposite to the connector portion toward the upstream side with respect to the mainstream flow direction A, and allows the fluid to be measured to flow into the measurement passage 5. The outlet 31 opens at the end surface of the flow rate measuring device 4 on the side opposite to the connector portion, and allows the fluid to be measured to flow out of the measurement passage 5. The end surface of the flow rate measuring device 4 on the side opposite to the connector portion is a surface substantially parallel to the mainstream flow direction A.

そして、第1通路22が、流入口21から第1屈曲部23に至るように主流の流れ方向Aに延設されている。第2通路24が、第1屈曲部23から第2屈曲部25に至るように主流の流れ方向Aと略直交する方向に回路基板7に向かって延設されている。第3通路26が、回路収納部12に近接して、第2屈曲部25から第3屈曲部27に至るように主流の流れ方向Aに延設されている。第4通路28が、第3屈曲部27から第4屈曲部29に至るように主流の流れ方向Aと略直交する方向に回路基板7から離れるように延設されている。第5通路30が、第4屈曲部29から主流の流れ方向Aとは逆方向に延びて流出口31に至るように延設されている。第1屈曲部23、第2屈曲部25、第3屈曲部27および第4屈曲部29は、被計測流体の流れ方向をほぼ90°曲げる部位であり、それぞれの内周壁面および外周壁面は所定の曲率半径の円弧状に形成されている。 The first passage 22 is extended in the mainstream flow direction A so as to reach the first bent portion 23 from the inlet 21. The second passage 24 extends toward the circuit board 7 in a direction substantially orthogonal to the mainstream flow direction A so as to reach the second bent portion 25 from the first bent portion 23. The third passage 26 extends in the mainstream flow direction A so as to approach the circuit housing portion 12 and reach from the second bent portion 25 to the third bent portion 27. The fourth passage 28 extends from the circuit board 7 in a direction substantially orthogonal to the mainstream flow direction A so as to reach from the third bent portion 27 to the fourth bent portion 29. The fifth passage 30 extends from the fourth bent portion 29 so as to extend in the direction opposite to the mainstream flow direction A and reach the outflow port 31. The first bent portion 23, the second bent portion 25, the third bent portion 27, and the fourth bent portion 29 are portions that bend the flow direction of the fluid to be measured by approximately 90 °, and the inner peripheral wall surface and the outer peripheral wall surface are predetermined. It is formed in an arc shape with a radius of curvature of.

また、円弧状の抑制板32が、第2通路24と第3通路26とを連結する第2屈曲部25に形成されており、第1屈曲部23で生じ、さらに第2屈曲部25で生じる2次流れを抑制する。また、第1連通穴33が、流量検出素子6の下流側の位置で、第3通路26と主通路1とを連通するように、金属プレート8に穿設されている。さらに、排水用溝34が、第3通路26の反回路基板側の壁面に沿って、第2屈曲部25から第3屈曲部27に至るように金属プレート8に凹設されている。
また、流量検出素子6の流量検出抵抗6bおよび温度補償用抵抗6cの形成領域が、計測用通路5の第3通路26内に露出している。そして、流量検出素子6は、流量検出部である流量検出抵抗6bが主流の流れ方向Aと直交する方向で、かつ、回路基板7と接離する方向における第3通路26の中心に対して、回路基板7側にシフトするように配設されている。
An arc-shaped suppression plate 32 is formed in the second bent portion 25 that connects the second passage 24 and the third passage 26, and is generated in the first bent portion 23 and further in the second bent portion 25. Secondary flow is suppressed. Further, the first communication hole 33 is formed in the metal plate 8 so as to communicate the third passage 26 and the main passage 1 at a position downstream of the flow rate detection element 6. Further, the drainage groove 34 is recessed in the metal plate 8 so as to extend from the second bent portion 25 to the third bent portion 27 along the wall surface of the third passage 26 on the side opposite to the circuit board.
In addition, the formation region of the flow rate detection resistor 6 b and the temperature compensation resistor 6 c of the flow rate detection element 6 is exposed in the third passage 26 of the measurement passage 5. The flow rate detection element 6 is a direction in which the flow rate detection resistor 6b, which is a flow rate detection unit, is orthogonal to the mainstream flow direction A and the center of the third passage 26 in the direction in which the flow rate detection element 6 is in contact with and away from the circuit board 7. It arrange | positions so that it may shift to the circuit board 7 side.

また、複数本のインサート導体20が、各一端20aを回路収納部12内に露出させ、各他端20bをコネクタ部11内に露出するように、ベース9にインサート成形されている。そして、流量検出素子6の入出力端子6dと回路基板7の電極端子7aとがワイヤ14を用いてワイヤボンディングされ、回路基板7の電極端子7aとインサート導体20の一端20aとがワイヤ14を用いてワイヤボンディングされている。なお、電気的接続の手法としてワイヤボンディングの例を説明しているが、溶接、半田付けなどの電気的接続方法を用いてもよい。
さらに、樹脂製のカバー15が、回路収納部12の外周溝18に塗布された接着剤19により接着されて回路収納部12を塞口している。ここで、図示していないが、封止用ゲルが回路収納部12に充填されている。
A plurality of insert conductors 20 are insert-molded in the base 9 so that each end 20 a is exposed in the circuit housing portion 12 and each other end 20 b is exposed in the connector portion 11. The input / output terminal 6d of the flow rate detection element 6 and the electrode terminal 7a of the circuit board 7 are wire-bonded using a wire 14, and the electrode terminal 7a of the circuit board 7 and one end 20a of the insert conductor 20 are used of the wire 14. Wire bonding. In addition, although the example of wire bonding is demonstrated as a method of electrical connection, you may use electrical connection methods, such as welding and soldering.
Further, a resin cover 15 is adhered by an adhesive 19 applied to the outer peripheral groove 18 of the circuit housing portion 12 to close the circuit housing portion 12. Here, although not shown, the sealing gel is filled in the circuit housing portion 12.

このように構成された流量測定装置4は、接合部10の他端側に位置するベース9の延出部、金属プレート8、計測用通路構成部13およびカバー15からなる本体部が、その延出方向と直交する断面を矩形とする直方体に形成されている。そして、本体部が、接合部10の延出方向の投影面内に包含されている。また、本体部の延出方向と直交する矩形断面の長辺で構成される一方の壁面が金属プレート8の裏面で、他方の壁面が計測用通路構成部13の他面およびカバー15の表面で構成されている。さらに、計測用通路5の流入口21が本体部の延出方向と直交する矩形断面の短辺で構成される一方の壁面の他端部近傍、即ち本体部の延出方向の先端部近傍に形成され、計測用通路5の流出口31が本体部の延出方向の端面に形成されている。   The flow rate measuring device 4 configured in this way has an extension portion of the base 9 located on the other end side of the joint portion 10, a main body portion made up of the metal plate 8, the measurement passage configuration portion 13 and the cover 15. It is formed in a rectangular parallelepiped having a rectangular cross section orthogonal to the outgoing direction. And the main-body part is included in the projection surface of the extension direction of the junction part 10. FIG. Further, one wall surface constituted by the long side of the rectangular cross section orthogonal to the extending direction of the main body portion is the back surface of the metal plate 8, and the other wall surface is the other surface of the measurement path constituting portion 13 and the surface of the cover 15. It is configured. Further, the inlet 21 of the measurement passage 5 is near the other end of one wall surface constituted by the short side of the rectangular cross section orthogonal to the extending direction of the main body, that is, near the tip of the main body extending in the extending direction. The outlet 31 of the measurement passage 5 is formed on the end surface of the main body in the extending direction.

この流量測定装置4は、本体部を主通路1内に延出するように挿入穴2に挿入され、接合部10のフランジ部を主通路1のフランジ部3にネジ16により締着固定されて取り付けられる。この流量測定装置4は、本体部の延出方向と直交する矩形断面の長辺で構成される壁面が主通路1内を流通する被計測流体の主流の流れ方向Aとほぼ平行となるように、かつ、本体部の矩形断面の短辺で構成される一方の壁面が流れ方向Aと直交するように上流側に向いて、主通路1にプラグインされている。そして、Oリング17が接合部10と挿入穴2との間に介装され、気密性が確保されている。この時、計測用通路5の流入口21は、主流の流れ方向Aと直交する面の、主通路1内への延出側端部近傍に開口し、流出口31は、主流の流れ方向Aと平行な面である主通路1内への延出側端面に開口している。   The flow rate measuring device 4 is inserted into the insertion hole 2 so that the main body portion extends into the main passage 1, and the flange portion of the joint portion 10 is fastened and fixed to the flange portion 3 of the main passage 1 with screws 16. It is attached. In the flow rate measuring device 4, the wall surface constituted by the long side of the rectangular cross section orthogonal to the extending direction of the main body is substantially parallel to the flow direction A of the main flow of the fluid to be measured flowing in the main passage 1. And one wall surface comprised by the short side of the rectangular cross section of a main-body part faces the upstream side so that it may orthogonally cross the flow direction A, and it is plugged in to the main channel | path 1. As shown in FIG. And the O-ring 17 is interposed between the junction part 10 and the insertion hole 2, and airtightness is ensured. At this time, the inlet 21 of the measurement passage 5 opens in the vicinity of the end on the side of the main passage 1 that is orthogonal to the mainstream flow direction A, and the outlet 31 extends in the mainstream flow direction A. Is open to the end surface of the main passage 1 that is parallel to the main passage 1.

そして、主通路1内を流通する被計測流体は、流入口21から計測用通路5内に流れ込み、第1通路22内を主流の流れ方向Aに流れ、第1屈曲部23により流れ方向をほぼ90°曲げられて第2通路24内を主流の流れ方向Aと直交する方向に流れる。ついで、被計測流体は、第2屈曲部25により流れ方向をほぼ90°曲げられ、第3通路26内を主流の流れ方向Aに流れ、流量検出素子6の表面に沿って流れる。その後、被計測流体は、第3屈曲部27により流れ方向をほぼ90°曲げられ、第4通路28内を主流の流れ方向Aと直交する方向に流れる。さらに、被計測流体は、第4屈曲部29により流れ方向をほぼ90°曲げられ、第5通路30内を主流の流れ方向Aと逆方向に流れ、流出口31から主通路1内に排出される。   Then, the fluid to be measured flowing in the main passage 1 flows into the measurement passage 5 from the inlet 21, flows in the first passage 22 in the mainstream flow direction A, and the flow direction is substantially changed by the first bent portion 23. It is bent by 90 ° and flows in the second passage 24 in a direction perpendicular to the mainstream flow direction A. Next, the fluid to be measured is bent by approximately 90 ° in the flow direction by the second bent portion 25, flows in the third flow path 26 in the main flow direction A, and flows along the surface of the flow rate detection element 6. Thereafter, the fluid to be measured is bent by approximately 90 ° in the flow direction by the third bent portion 27 and flows in the fourth passage 28 in a direction perpendicular to the mainstream flow direction A. Further, the fluid to be measured is bent by approximately 90 ° in the flow direction by the fourth bent portion 29, flows in the fifth passage 30 in the direction opposite to the main flow direction A, and is discharged from the outlet 31 into the main passage 1. The

そして、外部の電力がコネクタ部11からインサート導体20を介して回路基板7に構成された制御回路に供給される。この制御回路は、例えば温度補償用抵抗6cにて検出された被計測流体の温度に対して所定温度高くなるように流量検出抵抗6bへの通電電流を制御する。   Then, external power is supplied from the connector portion 11 to the control circuit formed on the circuit board 7 via the insert conductor 20. For example, the control circuit controls the energization current to the flow rate detection resistor 6b so as to be higher by a predetermined temperature than the temperature of the fluid to be measured detected by the temperature compensation resistor 6c.

このとき、被計測流体の流量が大きくなれば、流量検出抵抗6bから被計測流体に伝達される熱量が大きくなり、流量検出抵抗6bの温度が低下する。そこで、制御回路が被計測流体に伝達された熱量を補うように流量検出抵抗6bへの通電量を増加し、流量検出抵抗6bの温度が所定温度に維持される。逆に、被計測流体の流量が少なくなれば、流量検出抵抗6bから被計測流体に伝達される熱量が少なくなり、流量検出抵抗6bの温度が上昇する。そこで、制御回路が流量検出抵抗6bへの通電量を減少し、流量検出抵抗6bの温度が所定温度に維持される。
そして、この流量検出抵抗6bへの通電電流値を検出して、被計測流体の流量信号として出力され、所定の通路断面積を有する計測用通路5内を流れる被計測流体の流量が測定される。同様にして、被計測流体の流速も測定することもできる。
At this time, if the flow rate of the fluid to be measured increases, the amount of heat transferred from the flow rate detection resistor 6b to the fluid to be measured increases, and the temperature of the flow rate detection resistor 6b decreases. Therefore, the energization amount to the flow rate detection resistor 6b is increased so that the control circuit supplements the heat amount transmitted to the fluid to be measured, and the temperature of the flow rate detection resistor 6b is maintained at a predetermined temperature. Conversely, when the flow rate of the fluid to be measured decreases, the amount of heat transferred from the flow rate detection resistor 6b to the fluid to be measured decreases, and the temperature of the flow rate detection resistor 6b increases. Therefore, the control circuit decreases the energization amount to the flow rate detection resistor 6b, and the temperature of the flow rate detection resistor 6b is maintained at a predetermined temperature.
Then, the value of the current flowing through the flow rate detection resistor 6b is detected and output as a flow rate signal of the fluid to be measured, and the flow rate of the fluid to be measured flowing through the measurement passage 5 having a predetermined passage cross-sectional area is measured. . Similarly, the flow velocity of the fluid to be measured can also be measured.

この実施の形態1によれば、流入口21から流量検出素子6が配設された第3通路26に至る通路中に、第1屈曲部23および第2屈曲部25を配設しているので、被計測流体は、流れ方向を第1屈曲部23および第2屈曲部25でほぼ90°曲げられる。このとき、被計測流体内にダスト等の異物が含まれていると、異物は慣性質量が大きいため、第1屈曲部23および第2屈曲部25に衝突して減速される。そこで、第3通路26に到達した異物は十分に減速されており、仮に異物が流量検出素子6に衝突したとしても、その衝突エネルギーは小さく、流量検出素子6の耐久性および寿命が向上される。   According to the first embodiment, the first bent portion 23 and the second bent portion 25 are disposed in the passage from the inlet 21 to the third passage 26 where the flow rate detecting element 6 is disposed. The fluid to be measured is bent by approximately 90 ° in the flow direction at the first bent portion 23 and the second bent portion 25. At this time, if a foreign substance such as dust is contained in the fluid to be measured, the foreign substance has a large inertial mass, and therefore collides with the first bent part 23 and the second bent part 25 and is decelerated. Therefore, the foreign matter that has reached the third passage 26 is sufficiently decelerated, and even if the foreign matter collides with the flow rate detection element 6, the collision energy is small, and the durability and life of the flow rate detection element 6 are improved. .

また、内燃機関の主通路1内を流れる主流は、内燃機関の吸気バルブの開閉に伴って脈動流になる。このときの脈動の大きさは、エンジンのスロットルバルブ(絞り弁)の開度が小さい時は相対的に小さく、スロットルバルブの開度が大きくなるにつれて大きくなり、更に主流の流量の増加に伴っても大きくなる。そして、この脈動がある程度大きくなると、主流から迂回する計測用通路を具備しない流量測定装置の場合、流量検出抵抗6bによる流量計測がもつ非線形特性および流量検出抵抗6b自身がもつ応答遅れ特性のため、マイナスの誤差(リーン化誤差)を生じる。そこで、従来は、主流から迂回する計測用通路を具備することにより、慣性効果により計測用通路内の脈動を低減し、上述のマイナスの誤差を低減していた。
この流量測定装置4では、計測用通路5が、主流の流れ方向Aと本体部の延出方向とを含む平面内で屈曲して流入口21から流出口31に至るように構成されているので、本体部の延出方向の先端側の計測用通路構成部13の限られたスペースの中で、流入口21から流出口31までの通路長さをできる限り長くできる。これにより、より大きな慣性効果を効果的に得ることができ、上述のマイナスの誤差をより一層低減できる。つまり、流量検出抵抗6bによる流量計測がもつ非線形特性および流量検出抵抗6b自身がもつ応答遅れ特性に起因してリーン化された流量検出素子6の出力値は、計測用通路5の通路形状によりリッチ側に補正され、流量測定誤差が低減される。
Further, the main flow flowing in the main passage 1 of the internal combustion engine becomes a pulsating flow as the intake valve of the internal combustion engine is opened and closed. The magnitude of the pulsation at this time is relatively small when the opening degree of the throttle valve (throttle valve) of the engine is small, increases as the opening degree of the throttle valve increases, and further, as the main flow rate increases. Also grows. And when this pulsation increases to some extent, in the case of a flow rate measuring device that does not have a measurement passage that bypasses the main flow, because of the non-linear characteristic of flow rate measurement by the flow rate detection resistor 6b and the response delay characteristic of the flow rate detection resistor 6b itself, A negative error (lean error) is generated. Therefore, conventionally, by providing a measurement passage that bypasses the mainstream, the pulsation in the measurement passage is reduced by the inertia effect, and the above-described negative error is reduced.
In this flow rate measuring device 4, the measurement passage 5 is configured to bend in a plane including the flow direction A of the main flow and the extending direction of the main body so as to reach from the inlet 21 to the outlet 31. The length of the passage from the inflow port 21 to the outflow port 31 can be made as long as possible in the limited space of the measurement passage constituting portion 13 on the distal end side in the extending direction of the main body. Thereby, a larger inertia effect can be effectively obtained, and the above-described negative error can be further reduced. That is, the output value of the flow rate detecting element 6 leaned due to the non-linear characteristic of the flow rate measurement by the flow rate detection resistor 6 b and the response delay characteristic of the flow rate detection resistor 6 b itself is rich due to the shape of the measurement passage 5. The flow measurement error is reduced.

また、内燃機関の主通路1内を流れる主流は、内燃機関の回転数に同期した周波数で脈動しており、その周波数が低い程、主通路1の軸心を中心とした径方向の流速分布は凸型となり、周波数が高い程流速分布は平坦化する。つまり、主通路1を流れる被計測流体の流量は同じでも、主通路1の径方向における流速分布が内燃機関の回転数に応じ変化してしまう。このように、吸入空気量が同じにも関わらず、回転数が変化して主通路1内の流速分布が変化しても、この流量測定装置4は計測用通路5の流入口21と流出口31が主通路1の径方向において近接した位置にあるため、計測用通路5の流入口21と流出口31の近傍の流速に差異が生じ難い。そこで、計測用通路5内に誘起される被計測流体の流れの流速に差異が生じ難く、流量測定装置4の流量測定誤差をさらに低減することができる。   Further, the main flow flowing in the main passage 1 of the internal combustion engine pulsates at a frequency synchronized with the rotational speed of the internal combustion engine, and the lower the frequency, the radial flow velocity distribution centering on the axis of the main passage 1. Becomes convex, and the higher the frequency, the flatter the flow velocity distribution. That is, even if the flow rate of the fluid to be measured flowing through the main passage 1 is the same, the flow velocity distribution in the radial direction of the main passage 1 changes according to the rotational speed of the internal combustion engine. In this way, even if the intake air amount is the same, even if the rotational speed changes and the flow velocity distribution in the main passage 1 changes, the flow rate measuring device 4 is connected to the inlet 21 and the outlet of the measurement passage 5. Since 31 is in a position close to the radial direction of the main passage 1, it is difficult for a difference in flow speed between the inlet 21 and the outlet 31 of the measurement passage 5. Therefore, a difference in the flow velocity of the flow of the fluid to be measured induced in the measurement passage 5 hardly occurs, and the flow measurement error of the flow measuring device 4 can be further reduced.

また、この流量測定装置4は計測用通路5の流入口21と流出口31が主通路1の径方向において近接した位置にあるので、主通路1の内径が小さい場合でも、流入口21および流出口31を共に主通路1の軸心付近に配置することができる。そこで、内燃機関の回転数の変化による主通路1の径方向の流速分布が変化しても、計測用通路5内の流速差が最小限に抑制されるので、流量測定誤差を低減することができ好適である。
さらに、主通路1内にこの流量測定装置4を配置する場合、少なくとも流入口21と流出口31が配設されている流量測定装置4の端部近傍を主通路1内に突出するだけで流量測定が可能である。これにより、主通路1の径方向において、流量測定装置4の突出長さを最小限にすることができる。そこで、流量測定装置4を主通路1内に突出することにより生じる圧力損失を最小限に小さくすることができる。
In addition, since the flow rate measuring device 4 has the inlet 21 and the outlet 31 of the measurement passage 5 close to each other in the radial direction of the main passage 1, even if the inner diameter of the main passage 1 is small, Both outlets 31 can be arranged near the axis of the main passage 1. Therefore, even if the radial flow velocity distribution of the main passage 1 changes due to the change in the rotational speed of the internal combustion engine, the flow velocity difference in the measurement passage 5 is suppressed to the minimum, so that the flow measurement error can be reduced. This is preferable.
Further, when the flow rate measuring device 4 is disposed in the main passage 1, the flow rate is measured only by projecting into the main passage 1 at least the vicinity of the end of the flow rate measuring device 4 in which the inlet 21 and the outlet 31 are provided. Measurement is possible. Thereby, the protrusion length of the flow measuring device 4 can be minimized in the radial direction of the main passage 1. Therefore, the pressure loss caused by protruding the flow rate measuring device 4 into the main passage 1 can be minimized.

また、流量検出素子6の設置されている第3通路26の上流側の第2屈曲部25で、計測用通路5内の流れのベクトルは、略90°曲げられることにより、第2屈曲部25の外周側すなわち回路基板側で速く、内周側で遅い流速分布を呈することになる。
ここで、流量検出素子6に構成された流量検出抵抗6bは第3通路26の中心より回路基板側にシフトして配置されているので、流量測定は第2屈曲部25の内周側の流速の遅い、すなわち不安定な淀んだ流れの影響を受け難い。つまり、流量検出抵抗6bは比較的流速の速い個所に配置されているので、流量検出素子6の流量に対する感度が向上する。そこで、流量測定装置4の出力のいわゆるS/N比を上げることができる。
Further, the flow vector in the measurement passage 5 is bent by approximately 90 ° at the second bent portion 25 on the upstream side of the third passage 26 where the flow rate detecting element 6 is installed, so that the second bent portion 25 is bent. The flow velocity distribution is fast on the outer peripheral side, that is, on the circuit board side, and slow on the inner peripheral side.
Here, since the flow rate detection resistor 6 b configured in the flow rate detection element 6 is arranged shifted from the center of the third passage 26 toward the circuit board, the flow rate measurement is performed on the inner peripheral side of the second bent portion 25. It is difficult to be affected by the slow or unstable stagnant flow. That is, since the flow rate detection resistor 6b is disposed at a location where the flow velocity is relatively fast, the sensitivity of the flow rate detection element 6 to the flow rate is improved. Therefore, the so-called S / N ratio of the output of the flow rate measuring device 4 can be increased.

さらにまた、第1連通穴33が流量検出素子6の下流側で第3通路26と主通路1とを連通するように金属プレート8に穿設されているので、第3通路26を流れる被計測流体の一部が第1連通穴33から主通路1側に吸い出される。これにより、流量検出素子6の表面上の壁面境界層が薄くなり、結果的に第3通路26を流れる被計測流体の流速を上げることができ、流量検出素子6の流量に対する感度が向上する。そこで、流量測定装置4の出力のS/N比を上げることができる。   Furthermore, since the first communication hole 33 is formed in the metal plate 8 so as to communicate the third passage 26 and the main passage 1 on the downstream side of the flow rate detecting element 6, the measurement target flowing through the third passage 26 is provided. Part of the fluid is sucked out from the first communication hole 33 to the main passage 1 side. Thereby, the wall surface boundary layer on the surface of the flow rate detection element 6 becomes thin, and as a result, the flow velocity of the fluid to be measured flowing through the third passage 26 can be increased, and the sensitivity of the flow rate detection element 6 to the flow rate is improved. Therefore, the S / N ratio of the output of the flow rate measuring device 4 can be increased.

さらに、第1屈曲部23および第2屈曲部25においては、計測用通路5内の流れのベクトルが略90°曲げられることにより、各屈曲部23,25の外周側で速く、内周側で遅い流速分布を呈することになる。そして、第1屈曲部23では、このような流速分布に起因して、被計測流体が流速の遅い内周側から流速の速い外周側に流れる。これにより、第2通路24には、図5に矢印Bで示されるように、第2通路24の通路断面内で旋回する流速成分、即ち2次流れが発生する。同様に、第2屈曲部25でも、被計測流体が流速の遅い内周側から流速の速い外周側に流れ、2次流れが第3通路26に発生する。このような流れが流量検出素子6上に到達すると、本来測定しようとしている第3通路26内の主流の流れ方向Aと略平行な流れに重畳し、ノイズとなってしまう。この実施の形態1では、円弧状の抑制板(レール)32が第2屈曲部25に内周側と外周側とを分離するように配設されているので、被計測流体の内周側から外周側への流れが抑制板32により阻止され、2次流れの流量検出素子6上への到達が抑えられる。そこで、流量測定装置4の出力のS/N比を上げることができる。   Further, in the first bent portion 23 and the second bent portion 25, the flow vector in the measurement passage 5 is bent by approximately 90 °, so that it is faster on the outer peripheral side of each bent portion 23, 25 and on the inner peripheral side. It will exhibit a slow flow velocity distribution. In the first bent portion 23, due to such a flow velocity distribution, the fluid to be measured flows from the inner peripheral side where the flow velocity is low to the outer peripheral side where the flow velocity is high. As a result, as indicated by an arrow B in FIG. 5, a flow velocity component that swirls within the passage section of the second passage 24, that is, a secondary flow, is generated in the second passage 24. Similarly, in the second bent portion 25, the fluid to be measured flows from the inner peripheral side where the flow velocity is low to the outer peripheral side where the flow velocity is high, and a secondary flow is generated in the third passage 26. When such a flow reaches the flow rate detection element 6, it is superimposed on a flow substantially parallel to the flow direction A of the main flow in the third passage 26 to be originally measured, resulting in noise. In the first embodiment, since the arc-shaped suppression plate (rail) 32 is disposed in the second bent portion 25 so as to separate the inner peripheral side and the outer peripheral side, from the inner peripheral side of the fluid to be measured. The flow to the outer peripheral side is blocked by the suppression plate 32, and the arrival of the secondary flow on the flow rate detection element 6 is suppressed. Therefore, the S / N ratio of the output of the flow rate measuring device 4 can be increased.

また、自動車用内燃機関の吸入空気には水滴が含まれる場合があり、それが流量測定装置4の流量検出抵抗6bに付着すれば、流量測定装置4の出力変動が大きくなり、正確な流量測定が出来なくなる。この実施の形態1では、このような水滴は第1屈曲部23および第2屈曲部25の壁面に付着することになるが、特に第1および第2屈曲部23,25の内周側の流速の遅い淀んだ個所に溜まる。これらの水滴は、第3通路26の反回路基板側の壁面に沿って形成された排水用溝34に集められ、該排水用溝34に案内されて第3屈曲部25の下流に押し流される。そこで、水滴が流量検出素子6の流量検出抵抗6bに付着し難く、流量測定装置4の出力変動が抑制される。 Further, there are cases where water droplets are included in the intake air of the internal combustion engine for automobiles, and if it adheres to the flow rate detection resistor 6b of the flow rate measuring device 4, the output fluctuation of the flow rate measuring device 4 increases, and accurate flow rate measurement is performed. Cannot be done. In the first embodiment, such water droplets adhere to the wall surfaces of the first bent portion 23 and the second bent portion 25, and in particular, the flow velocity on the inner peripheral side of the first and second bent portions 23, 25. Accumulate in the late stagnation. These water droplets are collected in the drainage groove 34 formed along the wall surface of the third passage 26 on the side opposite to the circuit board, and are guided by the drainage groove 34 and pushed downstream of the third bent portion 25. Therefore, water droplets are unlikely to adhere to the flow rate detection resistor 6b of the flow rate detection element 6, and the output fluctuation of the flow rate measuring device 4 is suppressed.

また、流量検出素子6が金属プレート8に同一面位置となるように配設されているので、被計測流体は金属プレート8と流量検出素子6との境界で乱れを発生することがなく、正確な流量測定が可能となる。   Further, since the flow rate detecting element 6 is arranged on the metal plate 8 so as to be in the same plane position, the fluid to be measured does not generate a disturbance at the boundary between the metal plate 8 and the flow rate detecting element 6, and is accurate. It is possible to measure the flow rate.

また、自動車用内燃機関においては、吸気の慣性特性を利用し吸気効率を上げるために、排気行程の終わりに排気弁が閉じる前から吸気弁が開き始める場合がある。この場合、内燃機関の回転数やスロットル弁の開度がある条件となると、吸入空気が上流側に吹き返す、いわゆる逆流を含む脈動が発生する。流量測定装置が被計測流体の流れの向きを判別する機能を有しない場合、逆流を順流として検出するため、リッチ誤差を招いてしまう。
しかし、ここでは、流出口31が、主流の流れ方向Aと略平行な面である流量測定装置4の反コネクタ部側の端面に開口しているので、流出口31は主流の逆流方向とほぼ直交する方向に開口している。そこで、逆流を含む脈動が発生しても、被計測流体が流出口31から計測用通路5内に流入することが阻止される。また、第5通路30が、第4屈曲部29から主流の流れ方向Aとは逆方向に延びて流出口31に至るように延設されているので、仮に、被計測流体が流出口31から僅かに流入しても、流出口31から第5通路30内を逆流方向と反対方向に流れて減衰する。そこで、逆流を順流として検出して、リッチ誤差を招くこともない。
Further, in an automobile internal combustion engine, in order to increase the intake efficiency by utilizing the inertia characteristic of intake air, the intake valve may start to open before the exhaust valve closes at the end of the exhaust stroke. In this case, when conditions such as the number of revolutions of the internal combustion engine and the opening of the throttle valve are satisfied, pulsation including so-called back flow occurs in which the intake air blows back upstream. If the flow rate measuring device does not have a function of determining the direction of the flow of the fluid to be measured, a reverse error is detected as a forward flow, resulting in a rich error.
However, since the outlet 31 is open at the end surface on the side opposite to the connector portion of the flow rate measuring device 4 that is a surface substantially parallel to the mainstream flow direction A, the outlet 31 is substantially in the same direction as the mainstream reverse flow direction. Open in the orthogonal direction. Therefore, even if pulsation including backflow occurs, the fluid to be measured is prevented from flowing into the measurement passage 5 from the outlet 31. Further, since the fifth passage 30 extends from the fourth bent portion 29 so as to extend in the direction opposite to the mainstream flow direction A and reaches the outlet 31, temporarily, the fluid to be measured flows from the outlet 31. Even if it flows in slightly, it flows in the fifth passage 30 from the outlet 31 in the direction opposite to the reverse flow direction and attenuates. Therefore, the reverse flow is detected as a forward flow, and a rich error is not caused.

なお、上記実施の形態1では、排水用溝34が第3通路26の反回路基板側の壁面に沿って第2屈曲部25から第3屈曲部27に至るように金属プレート8に形成されているものとしているが、排水用溝は、第3通路26の反回路基板側の壁面に第2屈曲部25から第3屈曲部27に至るように形成してもよい。   In the first embodiment, the drain groove 34 is formed on the metal plate 8 so as to extend from the second bent portion 25 to the third bent portion 27 along the wall surface of the third passage 26 on the side opposite to the circuit board. However, the drain groove may be formed on the wall surface of the third passage 26 on the side opposite to the circuit board so as to reach from the second bent portion 25 to the third bent portion 27.

また、上記実施の形態1では、第1連通穴33が、流量検出素子6の下流位置で第3通路26と主通路1とを連通するように金属プレート8に穿設されているものとしているが、第1連通穴は、流量検出素子6の下流位置で第3通路26と主通路1とを連通するように、計測用通路構成部13に穿設してもよい。   In the first embodiment, the first communication hole 33 is formed in the metal plate 8 so as to communicate the third passage 26 and the main passage 1 at the downstream position of the flow rate detection element 6. However, the first communication hole may be formed in the measurement passage configuration portion 13 so as to communicate the third passage 26 and the main passage 1 at a position downstream of the flow rate detection element 6.

また、上記実施の形態1では、流出口31が、流量測定装置4の反コネクタ部側の端面に開口しているものとしているが、流出口は、主通路1の径方向に関して流入口21と近接し、かつ、主流の流れ方向Aと略平行な面に開口していればよく、例えば、第5通路30と主通路1とを連通するように金属プレート8あるいは計測用通路構成部13の反コネクタ部側の端部近傍に穿設してもよい。   Further, in the first embodiment, the outlet 31 is opened on the end surface of the flow rate measuring device 4 on the side opposite to the connector portion. The outlet is connected to the inlet 21 with respect to the radial direction of the main passage 1. For example, the metal plate 8 or the measurement passage component 13 may be open so that the fifth passage 30 and the main passage 1 communicate with each other. You may perforate in the end part vicinity by the side of a non-connector part.

実施の形態2.
図6はこの発明の実施の形態2に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。なお、各実施の形態において、横断面図は上記実施の形態1の図1と同様であるため割愛する。
Embodiment 2. FIG.
FIG. 6 is a partially broken side view showing a main part in a state in which the flow rate measuring device according to Embodiment 2 of the present invention is attached to the main passage. In each embodiment, the cross-sectional view is the same as that of FIG.

図6において、計測用通路5Aは、流入口21、第1通路22、第1屈曲部23、第2通路24、第2屈曲部25A、第3通路26A、第3屈曲部27A、第4通路28A、第4屈曲部29A、第5通路30および流出口31を備えている。
そして、第2屈曲部25A、第3屈曲部27Aおよび第4屈曲部29Aの外周壁面の曲率半径を大きくし、第2屈曲部25A、第3通路26A、第3屈曲部27A、第4通路28Aおよび第4屈曲部29Aの外周壁面を連続した円弧面に形成している。
なお、他の構成は上記実施の形態1と同様に構成されている。
In FIG. 6, the measurement passage 5A includes an inflow port 21, a first passage 22, a first bent portion 23, a second passage 24, a second bent portion 25A, a third passage 26A, a third bent portion 27A, and a fourth passage. 28A, the 4th bending part 29A, the 5th channel | path 30, and the outflow port 31 are provided.
And the curvature radius of the outer peripheral wall surface of 2nd bending part 25A, 3rd bending part 27A, and 4th bending part 29A is enlarged, 2nd bending part 25A, 3rd channel | path 26A, 3rd bending part 27A, 4th channel | path 28A. Further, the outer peripheral wall surface of the fourth bent portion 29A is formed in a continuous arc surface.
Other configurations are the same as those in the first embodiment.

このように構成された流量測定装置4Aでは、第2屈曲部25A、第3通路26A、第3屈曲部27A、第4通路28Aおよび第4屈曲部29Aの外周壁面が連続した滑らかな円弧面に構成されているので、計測用通路5A内を流れる被計測流体は連続した滑らかな円弧状の外周壁面に沿って曲げられ、計測用通路5A内に誘起される被計測流体の流れは乱れが少なくなる。そこで、流量検出素子6上の被計測流体の流れも乱れが少なく、計測用通路5A内の圧力損失も小さくなるので、計測用通路5A内を流れる被計測流体の流速が上がる。これにより、流量測定装置4Aの出力のS/N比が向上する。 In the flow rate measuring device 4A configured as described above, the outer peripheral wall surfaces of the second bent portion 25A, the third passage 26A, the third bent portion 27A, the fourth passage 28A, and the fourth bent portion 29A are formed into a smooth circular arc surface. which is configured, a fluid to be measured flowing through the measurement passage 5A is bent along a smooth arcuate outer peripheral wall surface of the continuous flow of the measurement fluid to be induced in the measurement passage 5A is less disturbed Become. Therefore, the flow of the fluid to be measured on the flow rate detecting element 6 is less disturbed and the pressure loss in the measurement passage 5A is reduced, so that the flow velocity of the fluid to be measured flowing in the measurement passage 5A is increased. Thereby, the S / N ratio of the output of the flow measuring device 4A is improved.

実施の形態3.
図7はこの発明の実施の形態3に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図7において、計測用通路5Bは、流入口21、第1通路22、第1屈曲部23B、第2通路24、第2屈曲部25B、第3通路26、第3屈曲部27B、第4通路28、第4屈曲部29、第5通路30および流出口31を備えている。
そして、第1屈曲部23B、第2屈曲部25Bおよび第3屈曲部27Bの外周壁面が、平坦面を、被計測流体をほぼ90°曲げるように傾斜させた斜面に形成されている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 3 FIG.
FIG. 7 is a partially broken side view showing a main part in a state in which the flow rate measuring device according to Embodiment 3 of the present invention is attached to the main passage.
In FIG. 7, the measurement passage 5B includes an inlet 21, a first passage 22, a first bent portion 23B, a second passage 24, a second bent portion 25B, a third passage 26, a third bent portion 27B, and a fourth passage. 28, a fourth bent portion 29, a fifth passage 30, and an outlet 31.
The outer peripheral wall surfaces of the first bent portion 23B, the second bent portion 25B, and the third bent portion 27B are formed as inclined surfaces that are inclined so that the measured fluid is bent by approximately 90 °.
Other configurations are the same as those in the first embodiment.

上記実施の形態1による流量測定装置4においては、第1屈曲部23の曲率半径が小さいと、第1屈曲部23の内周側の流速が遅くなり、不安定な淀みが発生することになる。なお、第2屈曲部25および第3屈曲部27の内周側にも、同様に、不安定な淀みが発生する。   In the flow rate measuring device 4 according to the first embodiment, if the radius of curvature of the first bent portion 23 is small, the flow velocity on the inner peripheral side of the first bent portion 23 becomes slow, and unstable stagnation occurs. . Similarly, unstable stagnation also occurs on the inner peripheral side of the second bent portion 25 and the third bent portion 27.

この実施の形態3による流量測定装置4Bでは、第1乃至第3屈曲部23B,25B,27Bの外周壁面、即ち上述の淀みに対向する面が斜面で形成されているので、計測用通路5Bの通路断面積が縮小される。それにより、第1乃至第3屈曲部23B,25B,27Bにおける計測用通路5Bの幅方向の壁面境界層が圧縮され、流速分布が矯正されるので、上述の淀みが小さくなる。その結果、計測用通路5B内に誘起される被計測流体の流れは、乱れが少なくなり、流量検出素子6上の流れも乱れが少なく、計測用通路5B内の圧力損失も小さくなり、流速が上がる。そこで、流量測定装置4Bの出力のS/N比が向上する。
なお、計測用通路5Bの幅方向とは、流量検出素子6の厚さ方向、即ち、図7中紙面と直交する方向である。
In the flow rate measuring device 4B according to the third embodiment, the outer peripheral wall surfaces of the first to third bent portions 23B, 25B, 27B, that is, the surfaces facing the above-mentioned stagnation are formed as slopes, so that the measurement passage 5B The passage cross-sectional area is reduced. Thereby, the wall surface boundary layer in the width direction of the measurement passage 5B in the first to third bent portions 23B, 25B, and 27B is compressed and the flow velocity distribution is corrected, so that the above-described stagnation is reduced. As a result, the flow of the fluid to be measured induced in the measurement passage 5B is less disturbed, the flow on the flow rate detecting element 6 is less disturbed, the pressure loss in the measurement passage 5B is also reduced, and the flow velocity is increased. Go up. Therefore, the S / N ratio of the output of the flow rate measuring device 4B is improved.
The width direction of the measurement passage 5B is the thickness direction of the flow rate detecting element 6, that is, the direction orthogonal to the paper surface in FIG.

実施の形態4.
図8はこの発明の実施の形態4に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図8において、計測用通路5Cは、流入口21、第1通路22、第1屈曲部23B、第2通路24C、第2屈曲部25C、第3通路26C、第3屈曲部27C、第4通路28C、第4屈曲部29、第5通路30および流出口31を備えている。
Embodiment 4 FIG.
FIG. 8 is a partially broken side view showing a main part in a state where a flow rate measuring device according to Embodiment 4 of the present invention is attached to the main passage.
In FIG. 8, the measurement passage 5C includes an inlet 21, a first passage 22, a first bent portion 23B, a second passage 24C, a second bent portion 25C, a third passage 26C, a third bent portion 27C, and a fourth passage. 28C, the 4th bending part 29, the 5th channel | path 30, and the outflow port 31 are provided.

そして、第1屈曲部23B、第2屈曲部25Cおよび第3屈曲部27Cの外周壁面は、平坦面を、被計測流体をほぼ90°曲げるように傾斜させた斜面に形成されている。また、第2通路24Cおよび第2屈曲部25Cを構成する計測用通路構成部13の計測用通路溝5aの深さが、第2通路24Cから第2屈曲部25Cを経て第3通路26Cの入口まで、連続的に漸次浅くなるように形成され、通路断面積が連続的に絞られる縮流部35,36を構成している。また、第3通路26Cおよび第3屈曲部27Cを構成する計測用通路溝5aの深さが、第3通路26Cの入口における計測用通路溝5aの深さに等しく形成されている。さらに、第4通路28Cを構成する計測用通路溝5aの深さが、第4通路28Cの通路入口から通路途中まで、連続的に漸次深くなるように形成され、通路断面積が連続的に拡大される拡大部37を構成している。
なお、他の構成は上記実施の形態3と同様に構成されている。
The outer peripheral wall surfaces of the first bent portion 23B, the second bent portion 25C, and the third bent portion 27C are formed as slopes in which flat surfaces are inclined so that the fluid to be measured is bent approximately 90 °. Further, the depth of the measurement passage groove 5a of the measurement passage constitution portion 13 constituting the second passage 24C and the second bent portion 25C is the entrance of the third passage 26C from the second passage 24C through the second bent portion 25C. The flow-reducing portions 35 and 36 are formed so as to become gradually shallower and the passage cross-sectional area is continuously reduced. Further, the depth of the measurement passage groove 5a constituting the third passage 26C and the third bent portion 27C is formed to be equal to the depth of the measurement passage groove 5a at the inlet of the third passage 26C. Furthermore, the depth of the measurement passage groove 5a constituting the fourth passage 28C is formed so as to be gradually deeper from the passage entrance to the middle of the passage of the fourth passage 28C, and the passage cross-sectional area continuously increases. The enlarged portion 37 is configured.
Other configurations are the same as those in the third embodiment.

このように構成された流量測定装置4Cでは、流量検出素子6は第3通路26Cの途中に計測用通路5Cを構成する壁面(金属プレート8の表面)と同一面位置に配設されており、該壁面上の被計測流体の流れを測定することになる。従って、縮流部35,36で流量検出素子6の厚さ方向に通路断面積を絞ることにより、流量検出素子6の厚さ方向における壁面境界層が圧縮され、流速分布が矯正される。そこで、流量検出素子6の上流近傍で流速が上がり、流量検出素子6上の流れも乱れが少なくなる。
また、流量検出素子6上を通過した流れは、拡大部37を通過する際に縮流部35,36で得られた動圧を徐々に静圧に変換されるので、静圧を均一化しながら回復する。これにより、壁面上の流体剥離が抑制され、計測用通路5C内の圧力損失を低減することができ、計測用通路5C内の流速が上がる。そこで、流量測定装置4Cの出力のS/N比が向上する。
In the flow rate measuring device 4C configured as described above, the flow rate detecting element 6 is disposed at the same plane position as the wall surface (the surface of the metal plate 8) constituting the measurement path 5C in the middle of the third path 26C. The flow of the fluid to be measured on the wall surface is measured. Therefore, by narrowing the passage cross-sectional area in the thickness direction of the flow rate detecting element 6 by the contracted portions 35 and 36, the wall surface boundary layer in the thickness direction of the flow rate detecting element 6 is compressed, and the flow velocity distribution is corrected. Therefore, the flow velocity increases in the vicinity of the upstream of the flow rate detection element 6 and the flow on the flow rate detection element 6 is less disturbed.
Further, the flow that has passed over the flow rate detecting element 6 is gradually converted into static pressure by the dynamic pressure obtained by the contraction portions 35 and 36 when passing through the enlarged portion 37, so that the static pressure is made uniform. Recover. Thereby, fluid separation on the wall surface is suppressed, pressure loss in the measurement passage 5C can be reduced, and the flow velocity in the measurement passage 5C is increased. Therefore, the S / N ratio of the output of the flow rate measuring device 4C is improved.

実施の形態5.
図9はこの発明の実施の形態5に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図9において、計測用通路5Dは、流入口21、第1通路22、第1屈曲部23、第2通路24、第2屈曲部25、第3通路26、第3屈曲部27、第4通路28D、通路断面積拡大部38および流出口31を備えている。そして、計測用通路5Dは、第4通路28Dが主流の流れ方向Aと略直交する方向に回路基板7から離れるように延設され、流出口31に直に接続されている。そして、通路断面積拡大部38は、主流の流れ方向Aおよび流量測定装置4Dの主通路1への延出方向を含め平面における断面形状を円形とし、第4通路28Dの上流側で、第4通路28Dおよび流出口31に接続するように設けられている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 5. FIG.
FIG. 9 is a partially cutaway side view showing a main part in a state where the flow rate measuring device according to Embodiment 5 of the present invention is attached to the main passage.
In FIG. 9, the measurement passage 5D includes an inlet 21, a first passage 22, a first bent portion 23, a second passage 24, a second bent portion 25, a third passage 26, a third bent portion 27, and a fourth passage. 28D, the passage cross-sectional area enlarged portion 38 and the outlet 31 are provided. The measurement passage 5 </ b> D extends so that the fourth passage 28 </ b> D is separated from the circuit board 7 in a direction substantially orthogonal to the mainstream flow direction A, and is directly connected to the outlet 31. The passage cross-sectional area expanding portion 38 has a circular cross-sectional shape in a plane including the flow direction A of the main flow and the extension direction of the flow rate measuring device 4D to the main passage 1, and the fourth cross-section is enlarged upstream of the fourth passage 28D. It is provided so as to be connected to the passage 28 </ b> D and the outlet 31.
Other configurations are the same as those in the first embodiment.

このように構成された流量測定装置4Dでは、通路断面積拡大部38が、第4通路28Dの上流側で、第4通路28および流出口31に接続されている。
そこで、逆流を含む脈動が発生し、被計測流体が流出口31から僅かに流入すると、まず通路断面積拡大部38に侵入する。そして、通路断面積拡大部38に侵入した被計測流体は、通路断面積拡大部38の円形断面形状により、図9中矢印Cで示される方向に旋回する。この通路断面積拡大部38内で旋回する被計測流体の流れは、第4通路28D内の被計測流体を流出口31から排出させる方向に加速するように作用する。これにより、被計測流体が、流出口31から逆流しにくくなる。そこで、逆流を順流として検出して、リッチ誤差を招くこともない。
In the flow rate measuring device 4D configured as described above, the passage cross-sectional area enlarged portion 38 is connected to the fourth passage 28 and the outlet 31 on the upstream side of the fourth passage 28D.
Therefore, when a pulsation including a back flow occurs and the fluid to be measured slightly enters the outlet 31, the fluid first enters the passage cross-sectional area enlarged portion 38. Then, the fluid to be measured that has entered the passage cross-sectional area enlarged portion 38 turns in the direction indicated by the arrow C in FIG. 9 due to the circular cross-sectional shape of the passage cross-sectional area enlarged portion 38. The flow of the fluid to be measured swirling in the passage cross-sectional area expanding portion 38 acts to accelerate the fluid to be measured in the fourth passage 28D in the direction of discharging from the outlet 31. Thereby, it becomes difficult for the fluid to be measured to flow backward from the outlet 31. Therefore, the reverse flow is detected as a forward flow, and a rich error is not caused.

実施の形態6.
図10はこの発明の実施の形態6に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図10において、計測用通路5Eは、流入口21、第1通路22、第1屈曲部23、第2通路24、第2屈曲部25、第3通路26、第3屈曲部27、第4通路28、第4屈曲部29、第5通路30、第2連通穴39および流出口31を備えている。そして、第2連通穴39は、穴方向を上流側に向かって回路収納部12から漸次離反するように主流の流れ方向Aに対して傾斜させて、第4屈曲部29と主通路1の計測用通路構成部13の下流側とを連通するように計測用通路構成部13に穿設されている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 6 FIG.
FIG. 10 is a partially broken side view showing a main part in a state where a flow rate measuring device according to Embodiment 6 of the present invention is attached to the main passage.
In FIG. 10, the measurement passage 5E includes an inlet 21, a first passage 22, a first bent portion 23, a second passage 24, a second bent portion 25, a third passage 26, a third bent portion 27, and a fourth passage. 28, a fourth bent portion 29, a fifth passage 30, a second communication hole 39, and an outflow port 31. The second communication hole 39 is inclined with respect to the flow direction A of the main flow so that the hole direction is gradually separated from the circuit housing portion 12 toward the upstream side, and the measurement of the fourth bent portion 29 and the main passage 1 is performed. The measurement passage constituting portion 13 is drilled so as to communicate with the downstream side of the use passage constituting portion 13.
Other configurations are the same as those in the first embodiment.

このように構成された流量測定装置4Eでは、逆流を含む脈動が発生すると、被計測流体(逆流)の一部が第2連通穴39から第4屈曲部29に侵入し、第4屈曲部29内の被計測流体を第5通路30を通って流出口31から排出させる方向に加速するように作用する。これにより、被計測流体が、流出口31から逆流しにくくなる。そこで、逆流を順流として検出して、リッチ誤差を招くこともない。   In the flow rate measuring device 4E configured as described above, when a pulsation including a backflow occurs, a part of the fluid to be measured (backflow) enters the fourth bent portion 29 from the second communication hole 39, and the fourth bent portion 29. The fluid to be measured is accelerated so as to be discharged from the outlet 31 through the fifth passage 30. Thereby, it becomes difficult for the fluid to be measured to flow backward from the outlet 31. Therefore, the reverse flow is detected as a forward flow, and a rich error is not caused.

実施の形態7.
図11はこの発明の実施の形態7に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図11において、計測用通路5Fは、穴方向を主流の流れ方向Aに一致させて、第4屈曲部29と主通路1の計測用通路構成部13の下流側とを連通するように計測用通路構成部13に穿設された第2連通穴39aを備えている。
なお、第2連通穴39に代えて第2連通穴39aを用いている点を除く他の構成は、上記実施の形態6と同様に構成されている。
Embodiment 7 FIG.
FIG. 11 is a partially broken side view showing a main part in a state where a flow rate measuring device according to Embodiment 7 of the present invention is attached to a main passage.
In FIG. 11, the measurement passage 5 </ b> F is for measurement so that the hole direction is aligned with the mainstream flow direction A and the fourth bent portion 29 communicates with the downstream side of the measurement passage configuration portion 13 of the main passage 1. A second communication hole 39a is provided in the passage component 13.
The other configuration except that the second communication hole 39a is used instead of the second communication hole 39 is the same as that of the sixth embodiment.

このように構成された流量測定装置4Fにおいても、逆流を含む脈動が発生すると、被計測流体(逆流)の一部が第2連通穴39aから第4屈曲部29に侵入し、第4屈曲部29内の被計測流体を第5通路30を通って流出口31から排出させる方向に加速するように作用する。これにより、被計測流体が、流出口31から逆流しにくくなり、上記実施の形態6と同様の効果が得られる。   Also in the flow rate measuring device 4F configured as described above, when a pulsation including a backflow occurs, a part of the fluid to be measured (backflow) enters the fourth bent portion 29 from the second communication hole 39a, and the fourth bent portion. It acts so as to accelerate the fluid to be measured in 29 in the direction of discharging from the outlet 31 through the fifth passage 30. Thereby, it becomes difficult for the fluid to be measured to flow backward from the outlet 31, and the same effect as in the sixth embodiment can be obtained.

実施の形態8.
図12はこの発明の実施の形態8に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図12において、隔壁40が、計測用通路構成部13の主流の流れ方向Aの全域に渡って、かつ、計測用通路構成部13の延出側端面に対して所定の間隙を持って、計測用通路構成部13に一体に形成されている。つまり、この隔壁40は、所定の隙間を持って計測用通路5の流出口31に対向するように配設されている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 8 FIG.
FIG. 12 is a partially cutaway side view showing a main part in a state where a flow rate measuring apparatus according to Embodiment 8 of the present invention is attached to the main passage.
In FIG. 12, the partition 40 is measured over the entire region in the mainstream flow direction A of the measurement passage component 13 and with a predetermined gap with respect to the extending side end surface of the measurement passage component 13. It is formed integrally with the passage structure portion 13 for use. That is, the partition wall 40 is disposed to face the outlet 31 of the measurement passage 5 with a predetermined gap.
Other configurations are the same as those in the first embodiment.

自動車用内燃機関においては、主流が流れる主通路1の内径は、内燃機関の吸入空気量の大小により、大小様々である。そして、上記実施の形態1による流量測定装置4を主通路1にプラグインする場合、流出口31と主通路1の内壁面との間の距離は、主通路1の内径により異なる。そして、流出口31近傍の被計測流体の流れの形態、さらには静圧に及ぼす影響度合いが、流出口31と主通路1の内壁面との間の距離により異なる。その結果、流量測定装置4の流量測定特性、つまり流量に対する出力の関係が主通路1の内径により異なり、主通路1の内径が異なっても流量測定特性が一元化できるプラグイン形態の長所が生かせない場合が生じる。   In the internal combustion engine for automobiles, the inner diameter of the main passage 1 through which the main flow flows varies depending on the intake air amount of the internal combustion engine. When the flow rate measuring device 4 according to the first embodiment is plugged into the main passage 1, the distance between the outlet 31 and the inner wall surface of the main passage 1 varies depending on the inner diameter of the main passage 1. The form of the flow of the fluid to be measured in the vicinity of the outlet 31 and the degree of influence on the static pressure differ depending on the distance between the outlet 31 and the inner wall surface of the main passage 1. As a result, the flow measurement characteristic of the flow measurement device 4, that is, the relationship of the output with respect to the flow rate, differs depending on the inner diameter of the main passage 1. Cases arise.

このように構成された流量測定装置4Gでは、隔壁40が所定の隙間を持って流出口31に対向して形成されているので、流出口31から対向する隔壁40までの距離が常に一定に保たれる。これにより、流出口31近傍の静圧が安定するために、隔壁40の流れに及ぼす影響が常に一定にできる。そこで、主通路1の内径が異なっても、流量測定特性が一元化でき、プラグイン形態の長所が生かせる。   In the flow rate measuring device 4G configured as described above, since the partition wall 40 is formed to face the outlet 31 with a predetermined gap, the distance from the outlet 31 to the opposite partition 40 is always kept constant. Be drunk. Thereby, since the static pressure in the vicinity of the outlet 31 is stabilized, the influence on the flow of the partition wall 40 can always be made constant. Therefore, even if the inner diameter of the main passage 1 is different, the flow measurement characteristics can be unified, and the advantages of the plug-in form can be utilized.

実施の形態9.
図13はこの発明の実施の形態9に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図13において、隔壁40aは、計測用通路構成部13の流出口31に対向する領域に位置し、計測用通路構成部13の延出側端面に対して所定の間隙を持って、計測用通路構成部13に一体に形成されている。
なお、隔壁40に代えて隔壁40aを用いている点を除く他の構成は、上記実施の形態8と同様に構成されている。
Embodiment 9 FIG.
FIG. 13 is a partially broken side view showing a main part in a state in which a flow rate measuring device according to Embodiment 9 of the present invention is attached to a main passage.
In FIG. 13, the partition wall 40 a is located in a region facing the outlet 31 of the measurement passage component 13, has a predetermined gap with respect to the extending side end surface of the measurement passage component 13, and the measurement passage It is formed integrally with the component 13.
The remaining configuration except that the partition 40a is used in place of the partition 40 is the same as that of the eighth embodiment.

このように構成された流量測定装置4Hにおいても、隔壁40aが流出口31に対向して形成されているので、上記実施の形態8と同様の効果が得られる。   Also in the flow rate measuring device 4H configured as described above, the partition wall 40a is formed so as to face the outflow port 31, so that the same effect as in the eighth embodiment can be obtained.

実施の形態10.
図14はこの発明の実施の形態10に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図14において、傾斜面41が、回路基板7側から流出口31の直ぐ下流に至るように計測用通路構成部13の下流側端部に形成されている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 10 FIG.
FIG. 14 is a partially broken side view showing a main part in a state where a flow rate measuring device according to Embodiment 10 of the present invention is attached to a main passage.
In FIG. 14, the inclined surface 41 is formed at the downstream end of the measurement passage constituting portion 13 so as to reach the downstream immediately from the outlet 31 from the circuit board 7 side.
Other configurations are the same as those in the first embodiment.

このように構成された流量測定装置4Iでは、逆流を含む脈動が発生すると、被計測流体(逆流)の一部が、傾斜面41に沿って流出口31の真下に流れ、流出口31の付近の被計測流体を上流側に加速する。これにより、被計測流体が、流出口31から計測用通路5内に逆流しにくくなる。そこで、逆流を順流として検出して、リッチ誤差を招くこともない。   In the flow rate measuring device 4I configured as described above, when a pulsation including a backflow occurs, a part of the fluid to be measured (backflow) flows directly below the outlet 31 along the inclined surface 41, and in the vicinity of the outlet 31. Accelerate the fluid to be measured upstream. This makes it difficult for the fluid to be measured to flow backward from the outlet 31 into the measurement passage 5. Therefore, the reverse flow is detected as a forward flow, and a rich error is not caused.

実施の形態11.
図15はこの発明の実施の形態11に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。
図15において、突出部42が、計測用通路構成部13の流出口31の上流側近傍端部に突設されている。
なお、他の構成は上記実施の形態1と同様に構成されている。
Embodiment 11 FIG.
FIG. 15 is a partially broken side view showing a main part in a state in which the flow rate measuring device according to the eleventh embodiment of the present invention is attached to the main passage.
In FIG. 15, the protruding portion 42 protrudes from the upstream vicinity end of the outlet 31 of the measurement passage constituting portion 13.
Other configurations are the same as those in the first embodiment.

このように構成された流量測定装置4Jでは、流出口31の直上流が突出部42により遮られているので、流出口31の出口近傍が上流側の流れの影響を受け難くなり、流出口31の出口近傍の静圧が安定する。
従って、被計測流体の主流が乱れている場合でも、流出口31の出口近傍の静圧は安定しているので、動圧も安定化し、ひいては計測用通路5内の流れの乱れが小さくなり、安定化する。これにより、流量測定装置4Jの出力のS/N比が向上する。
また、逆流を含む脈動が発生すると、被計測流体(逆流)が、突出部42に衝突し、逆流の流速が減衰し、被計測流体が流出口31から計測用通路5内に流入しにくくなる。そこで、逆流を順流として検出して、リッチ誤差を招くこともない。
In the flow rate measuring device 4J configured in this way, since the upstream portion of the outlet 31 is blocked by the protruding portion 42, the vicinity of the outlet of the outlet 31 is hardly affected by the upstream flow, and the outlet 31 The static pressure in the vicinity of the outlet is stabilized.
Accordingly, even when the main flow of the fluid to be measured is disturbed, the static pressure in the vicinity of the outlet 31 is stable, so that the dynamic pressure is also stabilized, and the flow turbulence in the measurement passage 5 is reduced. Stabilize. Thereby, the S / N ratio of the output of the flow rate measuring device 4J is improved.
Further, when a pulsation including a backflow occurs, the fluid to be measured (backflow) collides with the protruding portion 42, the flow velocity of the backflow attenuates, and the fluid to be measured does not easily flow into the measurement passage 5 from the outlet 31. . Therefore, the reverse flow is detected as a forward flow, and a rich error is not caused.

この発明の実施の形態1に係る流量測定装置を主通路に取り付けた状態を示す横断面図である。It is a cross-sectional view which shows the state which attached the flow volume measuring apparatus which concerns on Embodiment 1 of this invention to the main channel | path. この発明の実施の形態1に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 1 of this invention to the main channel | path. 図1の流量検出素子周りを示す要部拡大図である。It is a principal part enlarged view which shows the flow volume detection element periphery of FIG. 図2の流量検出素子周りを示す要部拡大図である。FIG. 3 is an enlarged view showing a main part around the flow rate detecting element in FIG. 2. 図2のV−V矢視断面図である。FIG. 5 is a cross-sectional view taken along line VV in FIG. 2. この発明の実施の形態2に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 2 of this invention to the main channel | path. この発明の実施の形態3に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 3 of this invention to the main channel | path. この発明の実施の形態4に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 4 of this invention to the main channel | path. この発明の実施の形態5に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 5 of this invention to the main channel | path. この発明の実施の形態6に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 6 of this invention to the main channel | path. この発明の実施の形態7に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 7 of this invention to the main channel | path. この発明の実施の形態8に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow measuring device which concerns on Embodiment 8 of this invention to the main channel | path. この発明の実施の形態9に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 9 of this invention to the main channel | path. この発明の実施の形態10に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow measuring device which concerns on Embodiment 10 of this invention to the main channel | path. この発明の実施の形態11に係る流量測定装置を主通路に取り付けた状態の要部を示す一部破断側面図である。It is a partially broken side view which shows the principal part of the state which attached the flow volume measuring apparatus which concerns on Embodiment 11 of this invention to the main channel | path.

符号の説明Explanation of symbols

1 主通路、4,4A,4B,4C,4D,4E,4F,4G,4H,4I,4J 流量測定装置、5,5A,5B,5C,5D,5E,5F 計測用通路、6 流量検出素子、7 回路基板(制御回路)、8 金属プレート(本体部)、9 ベース(本体部)、12 回路収納部、13 計測用通路構成部(本体部)、15 カバー(本体部)、21 流入口、22 第1通路部、23,23B 第1屈曲部、24,24C 第2通路部、25,25A,25B,25C 第2屈曲部、26,26A,26C 第3通路部、27,27A,27B,27C 第3屈曲部、28,28A,28C,28D 第4通路部、29,29A 第4屈曲部、30 第5通路部、31 流出口、32 抑制板、33 第1連通穴、34 排水用溝、35,36 縮流部、37 拡大部、38 通路断面積拡大部、39,39a 第2連通穴、40,40a 隔壁、41 傾斜面、A 主流の流れ方向、B 2次流れ。   1 Main passage, 4, 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H, 4I, 4J Flow measurement device, 5, 5A, 5B, 5C, 5D, 5E, 5F Measurement passage, 6 Flow detection element 7 Circuit board (control circuit) 8 Metal plate (main body part) 9 Base (main body part) 12 Circuit housing part 13 Measurement passage component (main body part) 15 Cover (main body part) 21 Inlet , 22 1st passage part, 23, 23B 1st bending part, 24, 24C 2nd passage part, 25, 25A, 25B, 25C 2nd bending part, 26, 26A, 26C 3rd passage part, 27, 27A, 27B , 27C Third bent portion, 28, 28A, 28C, 28D Fourth passage portion, 29, 29A Fourth bent portion, 30 Fifth passage portion, 31 Outflow port, 32 Suppression plate, 33 First communication hole, 34 For drainage Groove, 35, 36 contraction part, 7 enlarged portion, 38 cross-sectional area expanding portion, 39 and 39a the second communication hole, 40, 40a septum 41 inclined surface, A main flow direction, B 2 primary flow.

Claims (7)

主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記第4通路部が、上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びて上記本体部の延出方向の端面に開口して上記流出口を構成し、
上記主流の流れ方向および上記本体部の延出方向を含む平面における断面形状を円形とする通路断面積拡大部が上記第4通路部の上流側に該第4通路部および上記流出口に接続するように形成されていることを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detection element is disposed in the third passage ;
The fourth passage portion extends from the third bent portion in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction, and opens to an end surface in the extending direction of the main body portion. Configure the outlet,
A passage cross-sectional area enlarged portion having a circular cross-sectional shape in a plane including the main flow direction and the extending direction of the main body portion is connected to the fourth passage portion and the outlet on the upstream side of the fourth passage portion. A flow rate measuring device formed as described above .
主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記計測用通路は矩形の通路断面に形成されており、
上記流量検出素子は平板状の形状を有しており、
該流量検出素子は計測用通路を構成する一壁面と同一面位置になるように設置されており、
上記第2通路部から上記第2屈曲部を経て上記第3通路部の上流側入口まで、上記流量検出素子の厚さ方向の上記計測用通路の高さを漸次変えて通路断面積を連続的に絞る縮流部を備えていることを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detection element is disposed in the third passage ;
The measurement passage is formed in a rectangular passage cross section,
The flow rate detecting element has a flat plate shape,
The flow rate detection element is installed so as to be flush with the one wall surface constituting the measurement passage,
The passage cross-sectional area is continuously changed by gradually changing the height of the measurement passage in the thickness direction of the flow rate detecting element from the second passage portion through the second bent portion to the upstream inlet of the third passage portion. A flow rate measuring device characterized by comprising a contraction portion that is narrowed down to a minimum.
上記第4通路部の上流側入口から下流側に、上記流量検出素子の厚さ方向の上記計測用通路の高さを漸次変えて通路断面積を連続的に拡大する拡大部をさらに備えていることを特徴とする請求項2記載の流量測定装置。 From the upstream inlet of the fourth passage portion to the downstream side, there is further provided an enlarged portion that continuously increases the passage cross-sectional area by gradually changing the height of the measurement passage in the thickness direction of the flow rate detecting element. The flow rate measuring device according to claim 2 . 主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記計測用通路は矩形の通路断面に形成されており、
上記流量検出素子は平板状の形状を有しており、
該流量検出素子は計測用通路を構成する一壁面と同一面位置になるように設置されており、
上記第4通路部の上流側入口から下流側に、上記流量検出素子の厚さ方向の上記計測用通路の高さを漸次変えて通路断面積を連続的に拡大する拡大部を備えていることを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected directly or via other passages in the outlet, the flow rate detecting element is disposed in the third passage,
The measurement passage is formed in a rectangular passage cross section,
The flow rate detecting element has a flat plate shape,
The flow rate detection element is installed so as to be flush with the one wall surface constituting the measurement passage,
From the upstream inlet to the downstream of the fourth passage portion, there is provided an enlarged portion that continuously increases the passage cross-sectional area by gradually changing the height of the measurement passage in the thickness direction of the flow rate detecting element . A flow measuring device characterized by the above.
主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記流量検出素子の下流近傍に、上記第3通路部と上記主通路とを連通する第1連通穴を設けたことを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detection element is disposed in the third passage ;
A flow rate measuring apparatus comprising a first communication hole that communicates the third passage portion and the main passage in the vicinity of the downstream of the flow rate detecting element .
主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記第3通路部の上記回路収納部と対向する壁面に沿って上記第2屈曲部から上記第3屈曲部に至るように排水用溝を設けたことを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detection element is disposed in the third passage ;
A flow rate measuring device , wherein a drainage groove is provided from the second bent portion to the third bent portion along a wall surface of the third passage portion facing the circuit housing portion .
主通路内に延出され、内部に回路収納部を備えた本体部と、
上記本体部の上記回路収納部の延出側に形成されて上記主通路を流通する被計測流体の一部を流通させる計測用通路と、
上記計測用通路内に配設された流量検出素子と、
上記回路収納部内に収納されて上記流量検出素子を駆動してその信号を処理する制御回路と、を有する流量測定装置において、
上記計測用通路は、
上記本体部の延出方向の端部近傍に位置し、かつ、上記被計測流体の主流の流れ方向の上流側に向いて該本体部の該主流の流れ方向と直交する面に開口する流入口と、
上記本体部の延出方向の端部近傍に位置し、かつ、該本体部の該主流の流れ方向と平行な面に開口する流出口と、
上記流入口から上記主流の流れ方向に沿って第1屈曲部まで延びる第1通路部と、
上記第1屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部に向かって第2屈曲部まで延びる第2通路部と、
上記第2屈曲部から上記主流の流れ方向に沿って第3屈曲部まで延びる第3通路部と、
上記第3屈曲部から上記主流の流れ方向と直交する方向に沿って上記回路収納部から離反する方向に延びる第4通路部と、を備え、
上記第4通路部が直接又は他の通路を介して上記流出口に接続され、上記流量検出素子が上記第3通路に配設されており、
上記本体部の下流側端部に上記回路収納部側から上記流出口近傍に至る傾斜面を形成していることを特徴とする流量測定装置。
A main body portion that extends into the main passage and has a circuit storage portion therein;
A measurement passage that is formed on the extension side of the circuit housing portion of the main body and distributes a part of the fluid to be measured that flows through the main passage;
A flow rate detecting element disposed in the measurement passage;
A flow rate measuring device having a control circuit housed in the circuit housing section and driving the flow rate detection element to process the signal;
The measurement passage is
An inflow port that is located in the vicinity of the end of the main body in the extending direction and opens to a surface perpendicular to the main flow direction of the main body toward the upstream side of the main flow direction of the fluid to be measured. When,
An outlet located near the end of the main body in the extending direction and opening in a plane parallel to the main flow direction of the main body;
A first passage portion extending from the inlet to the first bent portion along the flow direction of the main flow;
A second passage portion extending from the first bent portion to the second bent portion along the direction orthogonal to the mainstream flow direction toward the circuit accommodating portion;
A third passage portion extending from the second bent portion to the third bent portion along the mainstream flow direction;
A fourth passage portion extending in a direction away from the circuit housing portion along a direction orthogonal to the mainstream flow direction from the third bent portion,
The fourth passage portion is connected to the outflow port directly or through another passage, and the flow rate detection element is disposed in the third passage ;
A flow rate measuring device, wherein an inclined surface extending from the circuit housing portion side to the vicinity of the outlet is formed at a downstream end portion of the main body portion .
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9234817B2 (en) 2013-10-11 2016-01-12 Mitsubishi Electric Corporation Flow rate measuring apparatus
US9328686B2 (en) 2014-05-19 2016-05-03 Mitsubishi Electric Corporation Flow measuring device
US9506794B2 (en) 2014-10-27 2016-11-29 Mitsubishi Electric Corporation Flow rate measuring device

Families Citing this family (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006010374A1 (en) * 2006-03-03 2007-09-06 Mann + Hummel Gmbh Arrangement of an air mass meter on a flow channel
JP5026134B2 (en) 2007-03-30 2012-09-12 株式会社トーメーコーポレーション Corneal imaging apparatus and cornea imaging method
DE102007021025A1 (en) * 2007-05-04 2008-11-06 Continental Automotive Gmbh Air flow sensor
JP4426606B2 (en) * 2007-06-29 2010-03-03 三菱電機株式会社 Flow measuring device
JP5052275B2 (en) * 2007-09-20 2012-10-17 アズビル株式会社 Flow sensor mounting structure
JP4576444B2 (en) * 2008-03-31 2010-11-10 日立オートモティブシステムズ株式会社 Thermal flow meter
JP5047079B2 (en) * 2008-07-02 2012-10-10 三菱電機株式会社 Flow measuring device
DE102008049843B4 (en) * 2008-10-01 2010-10-14 Continental Automotive Gmbh Air mass sensor
JP2010101704A (en) * 2008-10-22 2010-05-06 Mitsubishi Electric Corp Flow measuring apparatus
JP5168223B2 (en) * 2009-05-01 2013-03-21 株式会社デンソー Air flow measurement device
JP5256264B2 (en) * 2010-09-03 2013-08-07 日立オートモティブシステムズ株式会社 Thermal air flow sensor
JP5170209B2 (en) * 2010-10-28 2013-03-27 株式会社デンソー Flow measuring device
JP5263324B2 (en) * 2011-03-24 2013-08-14 株式会社デンソー Air flow measurement device
JP5663447B2 (en) * 2011-09-30 2015-02-04 日立オートモティブシステムズ株式会社 Gas flow measuring device
JP5645880B2 (en) 2012-06-15 2014-12-24 日立オートモティブシステムズ株式会社 Thermal flow meter
JP5813584B2 (en) * 2012-06-15 2015-11-17 日立オートモティブシステムズ株式会社 Thermal flow meter
US9261388B2 (en) 2012-07-11 2016-02-16 Trane International Inc. Methods and systems to measure fluid flow
JP5852978B2 (en) * 2013-03-12 2016-02-03 日立オートモティブシステムズ株式会社 Thermal flow meter
DE102013219399B4 (en) * 2013-09-26 2023-01-05 Robert Bosch Gmbh Arrangement for plugging a sensor into a passage opening of a flow channel so that it cannot rotate
JP6438707B2 (en) * 2014-08-22 2018-12-19 日立オートモティブシステムズ株式会社 Thermal flow meter
JP6463245B2 (en) * 2015-09-30 2019-01-30 日立オートモティブシステムズ株式会社 Thermal flow meter
US10145716B2 (en) * 2016-03-16 2018-12-04 GM Global Technology Operations LLC Mass airflow sensor including one or more flow deflectors for inhibiting reverse airflow through the mass airflow sensor
JP7068095B2 (en) * 2018-08-14 2022-05-16 株式会社Soken Flow measuring device
JP2020051794A (en) * 2018-09-25 2020-04-02 株式会社Soken Flowrate measuring device
DE102021203219B3 (en) 2021-03-30 2022-06-23 Vitesco Technologies GmbH Air mass sensor and motor vehicle

Family Cites Families (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2694664B2 (en) * 1989-03-07 1997-12-24 株式会社日立製作所 Hot wire air flow meter and internal combustion engine equipped with the flow meter
US4993261A (en) * 1989-08-21 1991-02-19 General Motors Corporation Flowmeter with boundary layer control
US5081866A (en) * 1990-05-30 1992-01-21 Yamatake-Honeywell Co., Ltd. Respiratory air flowmeter
JPH07209051A (en) 1994-01-13 1995-08-11 Hitachi Ltd Air flow rate measuring device
JPH08240461A (en) 1995-03-07 1996-09-17 Hitachi Ltd Air flow rate measuring device
US5804718A (en) * 1996-04-24 1998-09-08 Denso Corporation Airflow meter having an inverted u-shape bypass passage
JP3310167B2 (en) * 1996-06-12 2002-07-29 株式会社ユニシアジェックス Gas flow measurement device
DE19815654A1 (en) * 1998-04-08 1999-10-14 Bosch Gmbh Robert Measuring device for measuring the mass of a medium flowing in a line
DE19927818C2 (en) * 1999-06-18 2003-10-23 Bosch Gmbh Robert Device for measuring the mass of a flowing medium
JP3770369B2 (en) 1999-06-21 2006-04-26 日本特殊陶業株式会社 Flow rate and flow rate measuring device
KR20010039993A (en) * 1999-10-06 2001-05-15 오카무라 가네오 Flow Rate and Flow Velocity Measurement Device
JP3602762B2 (en) * 1999-12-28 2004-12-15 株式会社日立ユニシアオートモティブ Flow measurement device
EP1128168A3 (en) * 2000-02-23 2002-07-03 Hitachi, Ltd. Measurement apparatus for measuring physical quantity such as fluid flow
JP2001255189A (en) * 2000-03-13 2001-09-21 Ngk Spark Plug Co Ltd Flow rate and flowing velocity measuring apparatus
DE10019149B4 (en) * 2000-04-18 2007-06-06 Robert Bosch Gmbh Device for determining at least one parameter of a flowing medium
JP3716163B2 (en) * 2000-06-16 2005-11-16 株式会社日立製作所 Air flow measurement device
JP2002122452A (en) * 2000-08-11 2002-04-26 Ngk Spark Plug Co Ltd Divided flow type flowmeter
DE10059421C2 (en) * 2000-11-30 2003-04-10 Bosch Gmbh Robert Device for determining at least one parameter of a flowing medium
JP3785319B2 (en) * 2000-12-11 2006-06-14 株式会社日立製作所 Flow measuring device
DE10135142A1 (en) * 2001-04-20 2002-10-31 Bosch Gmbh Robert Device for determining at least one parameter of a medium flowing in a line
JP2002333347A (en) * 2001-05-08 2002-11-22 Ngk Spark Plug Co Ltd Distributary flow meter
JP3785338B2 (en) * 2001-07-25 2006-06-14 株式会社日立製作所 Thermal flow meter
JP3797210B2 (en) 2001-12-11 2006-07-12 株式会社デンソー Flow measuring device
JP3709373B2 (en) * 2001-12-19 2005-10-26 株式会社日立製作所 Flow measuring device
JP2003315126A (en) 2002-04-18 2003-11-06 Hitachi Ltd Air flow meter
DE10245965B4 (en) * 2002-09-30 2021-06-02 Robert Bosch Gmbh Device for determining at least one parameter of a medium flowing in a line
DE10246069A1 (en) 2002-10-02 2004-04-15 Robert Bosch Gmbh Device for determining at least one parameter of a medium flowing in a line
DE10253970A1 (en) 2002-11-20 2004-06-03 Robert Bosch Gmbh Device for determining at least one parameter of a medium flowing in a line
US6973825B2 (en) * 2003-02-24 2005-12-13 Visteon Global Technologies, Inc. Hot-wire mass flow sensor with low-loss bypass passage
JP3718198B2 (en) * 2003-02-26 2005-11-16 株式会社日立製作所 Flow sensor
JP3848934B2 (en) * 2003-05-16 2006-11-22 三菱電機株式会社 Air flow measurement device
DE10348400A1 (en) * 2003-07-14 2005-02-03 Robert Bosch Gmbh Mass flow measurement device for a combustion engine air intake has a bypass channel with a mass flow sensor and an upstream flow guidance part that is aerodynamically shaped to generate favorable flow characteristics
JP4166705B2 (en) * 2004-01-13 2008-10-15 三菱電機株式会社 Air flow measurement device
JP4020208B2 (en) * 2004-11-30 2007-12-12 三菱電機株式会社 Flow measuring device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9234817B2 (en) 2013-10-11 2016-01-12 Mitsubishi Electric Corporation Flow rate measuring apparatus
US9328686B2 (en) 2014-05-19 2016-05-03 Mitsubishi Electric Corporation Flow measuring device
DE102014224609B4 (en) * 2014-05-19 2021-03-11 Mitsubishi Electric Corporation Flow measuring device
US9506794B2 (en) 2014-10-27 2016-11-29 Mitsubishi Electric Corporation Flow rate measuring device

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